Correct information is .. half the war won already


Staging of breast cancer

To decide which stage has the cancer reached, we need to define the following three points:

  • Tumour extent (T)

  • Nodal spread (N)

  • Metastatic (Distant) spread (M)

Tumour extent (T)

To stage the 'T' part, the surgeon will assess the size of the lump in the breast. Apart from the size, he has to see, whether the skin overlying the tumour is involved, whether the nipple is retracted, whether the tumour is densely 'adherent' to the underlying chest wall. After understanding all these factors, the 'T' part is staged. According to the latest classification by the AJCC (7th ed), the T classification is as follows:

  • T1: Tumour less than 2 cm in greatest dimension.

  • T2: Tumour more than 2 cm but less than 5 cm in greatest dimension.

  • T3: Tumour more than 5 cm in greatest dimension.

  • T4: Tumor of any size with direct extension to the chest wall and/or to the skin (ulceration or skin nodules)

T1 to T3 are 'operable' lesions. A tumour will keep on growing and ultimately involve the skin or underlying chest wall, and it then becomes T4 which is defined as 'locally advanced cancer', and is not good, since the moment the tumour involves overlying skin or underlying chest wall, it's propensity to recur back after treatment, and propensity to spread to distant sites is much more. Once a cancer is 'locally advanced', it is usually not amenable to direct surgery and will need to be treated by a chemotherapy first to with an aim to make it operable.

Nodal spread (N)

To stage the 'N' part, the surgeon will assess the spread of the cancer in the axilla, by inserting his fingers in the axilla and feeling for any enlarged lymph nodes in the axilla in all directions and also by 'insinuating' fingers deep in the arm pit. The gives a fair idea of the 'nodal' spread of the cancer. After assessment, the nodal spread (the N part ) is classified as follows:

  • N0: There are no enlarged 'nodes' in the axilla

  • N1: Nodes in the axilla are enlarged and can be felt, but they are mobile when the surgeon attempts to hold them between his thumb and fingers and move them in all directions.

  • N2: Nodes in the axilla are enlarged and can be felt by the surgeon, and they are attached to one another ('matted') or to surrounding structures.

  • N3: Enlarged nodes can be felt either below or above the collar bone on the same side, irrespective of nodes in the axilla.

Here again, as long as the nodes are mobile (N1), they can be operated upon primarily. But once the nodes become matted (N2) to one another or to surrounding structures, they come under definition of 'locally advanced breast cancer', and will need a prior chemotherapy followed by surgery (after reassessment of response).

Distant spread (M)

The distant spread is assessed by certain investigations like an ultrasonography of the abdomen to see for liver and other organs, an Xray of the chest (or if need be, a CT Scan) to see for lung involvement or collection of fluid in the chest, a bone scan to see for spread to bones, etc.

  • M0 There is no evidence of any distant spread of the cancer.

  • M1 Cancer has spread beyond the breast to any distant site, like the lung, brain, liver, bones etc.

Once the T, N and M status is known, the final clinical staging is done to decide upon further treatment. To note, this is only a clinical staging. Once surgery is done, the specimen is assessed in histopathology and the final T and N staging is done, which is the pathological staging, on which further treatment is based. The National Cancer Institute, US, has a good detailed staging on its site; to see it, please click HERE